Fossum, John A.
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Buku Teks
Economic and Social Commission for Asia and the Pacific, 1991
Buku Teks
Artikel Jurnal
Gazda, George M.
Allyn and Bacon , 1975
Buku Teks
edited by Janis B. Kupersmidt and Kenneth A. Dodge
American Psychology Association, 2005
Buku Teks